Use of this pattern in C

I was reviewing a C codebase and encountered this programming pattern frequently but am not sure of the utility:

int afun(float a, int b)
{
  int avar;
  float bvar;

  { /* why is this block needed? */
    for(int l=0;l<9;l++)
    {
      avar=avar+i*0.25;
    }
  }
}

I do not understand why an extra code block might be needed after declaring local variables.